It is responsible for an estimated half-trillion dollars in federal spending every year, is hated by nearly everyone who studies it and is based on an American lifestyle older than the space program.

Yet the figure known as the “poverty line” is almost certainly here to stay. That’s partly because a more accurate measure of who is poor could add millions of Americans to the rolls — something few lawmakers want to have happen on their watch.

… “There are better ways to measure,” said Robert Haveman, a professor of economics and public policy at the University of Wisconsin and an expert on poverty. “Nearly any one of them is a better indicator of true poverty than the one we use.”